(1) Field of the Invention
The present invention relates to a suppository base composition.
(2) Description of the Prior Art
Suppository is smaller than medicine for internal use in the amount of drug component to be decomposed by the action of acid, alkali, digestive enzyme and the like in the digestive fluid, and further does not cause gastroenteric trouble. Particularly, suppository has a merit that can be easily dosed to children. Moreover, when a systemic dosage of a medicine by injection causes serious ill effect, the ill effect can be decreased by a local dosage of a suppository only to the diseased portion, and further the human body can be free from the pain at the injection.
There are mainly used two kinds of suppository bases of polyethylene glycol (hereinafter, abbreviated as PEG) and trigryceride (hereinafter, abbreviated as TG) of fatty acid at present.
Both PEG and TG are excellent suppository bases, but when a suppository is produced by the use of highly hydrophilic PEG, only a highly polar drug component, which dissolves in PEG or disperses uniformly therein, can be used. While, when a suppository is produced by the use of TG, TG is highly lipophilic, and therefore only a non-polar drug component, which dissolves in TG or disperses uniformly therein, can be used. Moreover, PEG and TG have no compatibility with each other, and therefore they cannot be used in admixture, and it is difficult to use a polar drug component in combination with a non-polar drug component.
Further, in the suppository using TG, the suppository is melted by the body temperature to absorb the drug component into the human body. Therefore, the melting point of the suppository is set to a temperature near the body temperature, and the suppository is poor in the strength at high temperature. Therefore, it is necessary to storage the suppository in a cold and dark place in order to prevent the deformation of the shape, and the suppository has a risk of melting during its transportation.
The inventors have made various investigations in order to produce suppository bases free from these drawbacks, and found out that specifically limited alkylene oxide derivative is excellent as a suppository base and is able to mix PEG and TG, and invented a novel suppository base containing these three components.